我有一个recyclerView。当用户向右或向左滑动时执行某些操作。 请注意我不是要求回收者查看项目滑动,而是要求整个Recyclerview手势向左或向右。
为此,我扩展了View.OnTouchListener并试图获得如下手势
public class OnSwipeTouchListener implements View.OnTouchListener {
private final GestureDetector gestureDetector;
public OnSwipeTouchListener(Context ctx) {
gestureDetector = new GestureDetector(ctx, new GestureListener());
}
@Override
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}
private final class GestureListener extends GestureDetector.SimpleOnGestureListener {
private static final int SWIPE_THRESHOLD = 100;
private static final int SWIPE_VELOCITY_THRESHOLD = 100;
@Override
public boolean onDown(MotionEvent e) {
return true;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
boolean result = false;
try {
float diffY = e2.getY() - e1.getY();
float diffX = e2.getX() - e1.getX();
if (Math.abs(diffX) > Math.abs(diffY)) {
if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
if (diffX > 0) {
onSwipeRight();
} else {
onSwipeLeft();
}
result = true;
}
} /*else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
if (diffY > 0) {
onSwipeBottom();
} else {
onSwipeTop();
}
result = true;
}*/
} catch (Exception exception) {
exception.printStackTrace();
}
return result;
}
}
public void onSwipeRight() {
}
public void onSwipeLeft() {
}
/*public void onSwipeTop() {
}
public void onSwipeBottom() {
}
*/
}
然后将其用作
recyclerViewComponent.setOnTouchListener(new OnSwipeTouchListener(context){
@Override
public void onSwipeRight() {
super.onSwipeRight();
}
@Override
public void onSwipeLeft() {
super.onSwipeLeft();
}
});
但我没有得到回调。这有什么问题?
答案 0 :(得分:0)
根据官方Google doc,您在处理onInterceptTouchEvent
时必须使用ViewGroups
(RecyclerView
扩展ViewGroup
)。
因此,您必须扩展RecyclerView
类才能覆盖其onTouchInterceptTouchEvent
方法:
public class MyRecyclerView extends RecyclerView {
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
switch (MotionEventCompat.getActionMasked(ev)) {
case MotionEvent.ACTION_MOVE: {
[...]
}
}
}
}
然后,您还必须更改布局XML文件,以使用自定义RecyclerView
MyRecyclerView
。